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v3.20.4

Commitments and Contingencies (Details) $ in Millions, $ in Millions |  |  | 12 Months Ended |  |
--- | --- | --- | --- | --- | ---
Dec. 21, 2020 CAD ($) | Oct. 22, 2020 CAD ($) | Dec. 31, 2020 CAD ($) J | Dec. 31, 2019 CAD ($) | Dec. 31, 2018 CAD ($) | Dec. 31, 2020 CAD ($) | Dec. 31, 2020 terajoule | Dec. 31, 2020 USD ($) | Jul. 30, 2015 USD ($)
Disclosure of Commitments [Line Items] |  |  |  |  |  |  |  |  |
Transportation agreement, term |  |  | 15 years |  |  |  |  |  |
Long-term firm natural gas delivery transportation, amount transferred per day |  |  | 400 |  |  |  | 400 |  |
Minimum operating lease payments recognised as expense |  |  |  |  | $ 8 |  |  |  |
Sublease payments received (amounts less than) |  |  | $ 2 | $ 1 | $ 1 |  |  |  |
TransAlta Energy Transition Bill |  |  |  |  |  | $ 18 |  |  | $ 55
Funded portion of energy bill commitment |  |  |  |  |  |  |  | $ 41 |
Total payments, line loss proceedings | $ 11 | $ 6 | 25 |  |  |  |  |  |
Accrued payments, line loss proceedings |  |  | $ 8 |  |  |  |  |  |
Estimated financial effect of contingent liabilities |  |  |  |  |  | 12 |  |  |
Emissions performance credits allotted, per year, amount |  |  |  |  |  | 17 |  |  |
Loss contingency accrual |  |  |  |  |  | 22 |  |  |
Increase (decrease) in loss contingency accrual, percentage |  |  | 15.00% |  |  |  |  |  |
Increase (decrease) in loss contingency accrual |  |  |  |  |  | 3 |  |  |
AltaLink Management Ltd. [Member] |  |  |  |  |  |  |  |  |
Disclosure of Commitments [Line Items] |  |  |  |  |  |  |  |  |
Loss contingency accrual |  |  |  |  |  | $ 91 |  |  |
NOVA Gas Transmission Ltd. |  |  |  |  |  |  |  |  |
Disclosure of Commitments [Line Items] |  |  |  |  |  |  |  |  |
Long-term firm natural gas delivery transportation, amount transferred per day |  |  | 351 |  |  |  | 275 |  |
Tidewater |  |  |  |  |  |  |  |  |
Disclosure of Commitments [Line Items] |  |  |  |  |  |  |  |  |
Long-term firm natural gas delivery transportation, amount transferred per day |  |  | 139 |  |  |  | 139 |  |

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- Definition The amount of the estimated financial effect of contingent liabilities. [Refer: Contingent liabilities [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 37 -IssueDate 2019-01-01 -Paragraph 86 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=37&code=ifrs-tx-2019-en-r&anchor=para_86_a&doctype=Standard -URIDate 2019-03-27 + Details
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- Definition The amount of income from subleasing right-of-use assets. Sublease is a transaction for which an underlying asset is re-leased by a lessee (‘intermediate lessor’) to a third party, and the lease (‘head lease’) between the head lessor and lessee remains in effect. [Refer: Right-of-use assets] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 16 -IssueDate 2019-01-01 -Paragraph 53 -Subparagraph f -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=16&code=ifrs-tx-2019-en-r&anchor=para_53_f&doctype=Standard -URIDate 2019-03-27 + Details
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- Definition Commitment for Energy Bill Initiatives + References No definition available. + Details
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- Definition Emissions Performance Credits Allotted, Per Year, Amount + References No definition available. + Details
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- Definition The portion of operating lease payments that the lessee is or can be required to make, excluding contingent rent, costs for services and taxes to be paid by, and reimbursed to, the lessor, together with any amounts guaranteed by the lessee or by a party related to the lessee recognised as an expense. + References No definition available. + Details
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- Details
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